The present invention relates to a combination lock system comprising a set of push-buttons that can be actuated in compliance with a combination, a set of series of coders, in which each series is associated with a push-button, incrementing means for placing the coders of each series successively in a position to be operated by actuating a push-button, coding means for defining a waiting configuration of the coders in which the coders selected for the combination occupy a coding position and the coders not selected for the combination occupy an inactive position, actuation of the locking means of the lock being possible if the selected coders have been operated by actuating push-buttons in compliance with the combination, the system further comprising means for returning the coders to the waiting configuration after actuation of the push-buttons.
Each push-button is associated with a series of several coders, for example four or five coders. In a waiting position, each first coder of each series is ready to be operated by a corresponding push-button. As soon as a push-button has been depressed, the incrementing means place the second coders of each series in a position to be operated by the corresponding pushbutton, and so on. The incrementing means therefore enable the same push-button to be used more than once in the coded combination, up to a limit which is the number of coders in each series.
The push-buttons generally comprise numeric push-buttons and possibly two or three alphabetic push-buttons. Being able to use the same push-button more than once in the coded combination considerably increases the number of combinations available.
The lock can be opened when the correct combination has been entered by actuating the push-buttons. Otherwise the lock remains locked. In both cases the coders can be returned to a waiting position for a new attempt to open the lock.
U.S. Pat. No. 4,827,743 discloses a system of the above kind in which the coders are rotary coders and have two arms in a V arrangement. Depending on whether a coder is part of the coded combination or not, actuating the corresponding push-button moves the coder in one rotation direction or the other. Moving a coder in the xe2x80x9crightxe2x80x9d rotation direction unlocks the lock, which is not possible if a coder is moved in the xe2x80x9cwrongxe2x80x9d rotation direction.
The number of coders used in this kind of coded combination lock system can be very large. For example if the push-buttons comprise ten numeric push-buttons and each series of coders comprises five coders, not less than 50 coders will be necessary. Coding the combination necessitates putting all these coders in a correct position relative to each other, which, given their number, is difficult and time-consuming.
U.S. Pat. No. 4,827,743 uses the push-buttons for entering the combination to carry out the coding. To this end, the user obtains access to the coders from the inside of the lock, which is the side opposite that carrying the push-buttons, and then, by means of a pivoting panel, sets all the coders to the same inactive position. The user then enters the new combination by means of the push-buttons, which places the selected coders in an intermediate position in which they are offset angularly relative to the other coders. The user then closes the panel previously used to place all the coders in the inactive position; this movement of the panel entrains only the selected coders, increasing their angular offset relative to the coders that are not part of the combination and placing them in their coding position.
This system has the advantage of avoiding manual manipulation of all the coders. However, if a new code is entered by means of the push-buttons, all of the selected coders must first occupy an intermediate angular position before they have to be moved into a coding position by rotating the panel. In effecting this latter operation, the user must ensure that all the selected coders have been placed in their correct intermediate position, i.e. with a sufficient angular offset relative to the coders have not been selected for them to be selectively entrained in rotation by pivoting the panel. The user must in particular ensure that the push-buttons have been depressed sufficiently for all the selected coders to have been moved through a sufficient angular displacement relative to the coders that have not been selected and have remained in their intermediate position.
In the system disclosed in U.S. Pat. No. 4,827,743, depressing a push-button which is part of the combination moves the corresponding coder in a first rotation direction, the effect of which is to actuate a first flap which in turn, via two ratchet systems, moves an incrementation bar and a locking bar. Pressing a push-button that is not part of the combination moves the corresponding coder in a second rotation direction, which actuates a second flap which actuates the first flap via a connecting arm, the effect of which is to cause the first ratchet system to move the incrementation bar, but the connecting arm lifts a pawl which prevents incrementing the displacement of the locking bar.
The two push-buttons operate neither the same parts nor the same number of parts. Consequently, the aware user inevitably detects a tactile difference and an audible difference between the two push-buttons and can therefore recognize the one that is not part of the combination. There is therefore a risk that the code can eventually be detected.
The present invention applies to this type of coded combination lock and aims to simplify further the coding operation.
That aim is achieved by the invention providing a system comprising means for authorizing two actuation strokes of the push-buttons, namely a normal stroke and a coding stroke, the normal stroke being such that a push-button actuated over that stroke causes the movement of a selected coder from its coding position to a non-locking position or the movement of an unselected coder from its inactive position to a locking position preventing unlocking, while the coding stroke is such that a push-button actuated over that stroke causes a coder to be moved from its inactive position to its coding position and the system further comprising means which, to enable entry of a new coded combination, place all the coders in the inactive position and authorize actuation of the push-buttons over their coding stroke.
The normal stroke of the push-buttons is that allowed for entering the combination to open the locking means of the lock. The coding stroke is used only to change the combination. For this purpose, the authorized user actuates the means for authorizing the coding stroke, in general from the side of the lock that is inside the protected area (the inside of the door fitted with the lock). Before entering a new combination, the user places all the coders in the inactive position and then enters the new combination using the push-buttons, which are manipulated in exactly the same way as when using the lock normally, except that the stroke of the push-buttons is different from the normal stroke. Then, when the new combination has been entered, it is no longer necessary to move coders, and it is sufficient to reset the stroke of the push-buttons to the normal stroke and to reset the incrementing means, for example by actuating the door handle.
The coding stroke is preferably longer than the normal stroke of the push-buttons.
The displacement of a selected coder from its coding position to its unlocking position is preferably the same as the displacement of a selected coder from its inactive position to its locking position and actuating the push-buttons preferably affects only the incrementing means and the coders.
Accordingly, actuating a push-button that is part of the combination and actuating a push-button that is not part of the combination have exactly the same subjective effect, so the user cannot detect any difference, in particular any tactile or audible difference, between actuating the two push-buttons.
Each coder advantageously has spaced first and second unlocking markers and, in the unlocking position of a selected coder, the second unlocking marker of said coder is disposed in corresponding relationship with the first unlocking markers of the coders in the inactive position.
In this type of lock, unlocking is possible when all the coders have locking markers disposed in a corresponding relationship, generally aligned with each other. In their waiting position, the coders selected for the combination are offset relative to the inactive coders. The offset is such that, if the selected coders are moved to the unlocking position, the second unlocking markers of the selected coders come into corresponding relationship with the first unlocking markers of the unselected coders, which have remained in the inactive position. Accordingly, even in the unlocked position, the selected coders are offset relative to the unselected coders. This facilitates resetting, which consists of returning the coders to the waiting position after actuation of the push-buttons. This is because, at the time of a reset, the selected coders which are in the unlocking position are selectively moved to the coding position and any unselected coders that may happen to be in the locking position are returned to the inactive position.
In this case, it is advantageous if each coder has spaced first and second actuation surfaces respectively adapted to cooperate with a push-button in order, when the push-button is depressed, to cause the coder to be moved between its inactive position and its locking position and between its coding position and its unlocking position.
If actuating the push-button operates a selected coder, then the latter is moved from its coding position to its unlocking position. On the other hand, if actuating the push-button operates an unselected coder, it is moved from its inactive position to its locking position. These positions are offset relative to each other.
A push-button actuated in error moves an unselected coder in the same way that a push-button actuated in conformance with the combination moves a selected coder. Accordingly, all the push-buttons appear to react in the same way when actuated. A person entering an incorrect combination is therefore unable to identify the push-button actuated in error.
It is also advantageous if each coder has spaced first and second reset surfaces and the means for returning the coders to the waiting configuration after the push-buttons are actuated comprise a reset member adapted to co-operate with the first reset surfaces of the coders occupying the locking positions to return said coders to their inactive positions and to co-operate with the second reset surfaces of the coders occupying their unlocking positions to return said coders to their coding positions.
On the other hand, at the time of a reset, the reset member preferably moves neither the unselected coders that have remained in the inactive position nor the selected coders that have remained in the coding position. The resetting surfaces are therefore disposed so that the resetting surfaces of a coder in the inactive position escape from the resetting member in the same way that the resetting surfaces of a coder in the coding position escape from that member.
The system advantageously comprises coupling means between the operating means of the lock, such as a square operating shaft, and the locking means of the lock, said coupling means having a non-interlocked configuration at rest and means for placing the coupling means in an interlocked configuration if the push-buttons have been operated in compliance with the correct combination, in which interlocked configuration the locking means are coupled to the lock operating means.
Accordingly, if the correct combination has not been entered, the lock operating means are not interlocked with the locking means and turn freely if they are operated by the user, for example by means of a handle.
The user who has entered a combination on the push-buttons naturally attempts to verify if the combination is correct by attempting to open the lock by manipulating operating means such as the handle.
The means for returning the coders to the waiting position after actuation of the push-buttons advantageously comprise a reset member that can be actuated by manipulating the lock operating means.
The virtually inevitable actuation of the lock operating means is therefore exploited to perform the reset.
The system advantageously comprises a free passage function which enables actuation of the locking means of the lock by the operating means of the lock without actuating the push-buttons.
It is obviously preferable for activation of this free passage function to be possible only for an authorized user, and therefore preferably after correct use of the coded combination. This is the case in particular if the function can be activated only from the inside of the lock, inside the protected area. The free passage function momentarily bypasses the coders of the lock, as it were. For example, this enables the premises at whose entry the lock is provided to be protected at only certain times of day or only if the usual occupant is not present.